Cafago offers the iMicrophone Karaoke Wireless Bluetooth Condenser Microphone in Black or Gold for $46.98. Coupon code "V2724GDF" cuts that to $32.48. With free shipping, that's $34 off and the lowest total price we could find. It features volume and echo controls, a detachable 5-watt speaker, Bluetooth 4.0, 3.5mm auxiliary port, aluminum magnesium metal construction, and built-in rechargeable battery with up to five hours of run-time per charge.
Note: This item ships from mainland China and is expected to arrive within 7 to 20 business days.